ENGLISH
REFERENCE

encyclopedia

n.
US //ɪnˌsaɪkɫəˈpidiə// UK //ɛnsˌaɪkləʊpˈiːdiə// en·cy·clo·pe·dia
  1. 1 reference work (n.)
    B1 Intermediate

    a book or website that gives information on many subjects, often arranged from A to Z.

    a comprehensive reference work containing articles on various subjects, typically arranged alphabetically. While traditionally printed in multiple volumes, the term now frequently refers to digital databases.

    Example

    I looked up the history of Rome in the encyclopedia for my school project.

    Example

    Before the internet became the primary source of information, many families invested in a printed encyclopedia to help their children with research.
  2. 2 person with vast knowledge (n.)
    B2 Upper Intermediate Informal

    a person who knows a lot of facts about many different things.

    a person who possesses a vast and comprehensive range of knowledge. Often used metaphorically in the phrase 'a walking encyclopedia'.

    Example

    My grandfather is a walking encyclopedia when it comes to classic cars.

    Example

    The professor was a virtual encyclopedia of medieval history, able to cite obscure dates and names without ever consulting his notes.
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  1. 3 summary of knowledge (n.)
    C2 Proficiency Archaic Formal

    a complete summary of all the information in a specific area of study.

    a comprehensive summary of a specific branch of knowledge or the entire circle of arts and sciences.

    Example

    The old text was intended to be an encyclopedia of all medical knowledge at the time.

    Example

    The philosopher's ultimate ambition was to compile a complete encyclopedia of human reason, categorising every possible thought and emotion.
Origin

Etymology tree ▲ Proto-Indo-European *h₁en- Proto-Indo-European *h₁en- Proto-Indo-European *h₁én Ancient Greek ἐν (en) Ancient Greek ἐν- (en-) Proto-Indo-European *kʷel- Proto-Indo-European *kʷékʷlos Ancient Greek κύκλος (kúklos) Proto-Indo-European *-yósder. Ancient Greek -ιος (-ios) Ancient Greek ἐγκύκλῐος (enkúklĭos) Proto-Indo-European *peh₂w-der. Proto-Hellenic *pā́wits Ancient Greek παῖς (paîs) Ancient Greek -εύς (-eús) Ancient Greek -εύω (-eúō) Ancient Greek παιδεύω (paideúō) Proto-Indo-European *-h₂ Proto-Indo-European *-éh₂ Proto-Indo-European *-i-eh₂ Proto-Hellenic *-íā Ancient Greek -ία (-ía) Ancient Greek παιδείᾱ (paideíā) Ancient Greek ἐγκύκλιος παιδείᾱ (enkúklios paideíā)bor. New Latin encyclopaedīalbor. English encyclopedia Borrowed from New Latin encyclopēdīa, encyclopaedīa (“general education”), a univerbated form of Koine Greek ἐγκύκλιος παιδείᾱ (enkúklios paideíā, “education in the circle of arts and sciences”), from Ancient Greek ἐγκύκλιος (enkúklios, “circular”) + παιδείᾱ (paideíā, “childrearing; education”) (q.v.). Nearly all modern English usage of the word was influenced by the scope and format of the French Encyclopédie by Diderot et al. (see quotation).

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